A small population of retinal ganglion cells projecting to the retina of the other eye

The specification of central connexions of retinal ganglion cells was studied in Xenopus laevis. In one series of experiments, the right eye primordium was rotated 180° at embryonic stages 24–32. In the other series, the left eye was transplanted into the right orbit, and vice versa, with either 0° or 180° rotation. After metamorphosis the visual projections from the operated eye to the contralateral optic tectum were mapped electrophysiologically and compared with the normal retinotectal map. In all cases the visual projection map was rotated through the same angle as was indicated by the position of the choroidal fissure. The left eye exchanged into the right orbit retained its original axes and projected to the contralateral tectum. These results suggest that retinal ganglion cell connexions are specified before stage 24.

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Relation of Brightness to Threshold for Light-Adapted and Dark-Adapted Rods and Cones: Effects of Retinal Eccentricity and Target Size

Perception ◽

10.1068/p090633 ◽

1980 ◽

Vol 9 (6) ◽

pp. 633-650 ◽

Cited By ~ 4

Author(s):

Bruce Drum

Keyword(s):

Retinal Ganglion Cells ◽

Channel Model ◽

Ganglion Cells ◽

The Other ◽

Target Size ◽

Retinal Eccentricity ◽

Retinal Ganglion ◽

Threshold Functions ◽

Rods And Cones ◽

Matching Procedure

‘Equal-brightness' functions of retinal eccentricity and target diameter were measured by a matching procedure, and compared with the corresponding threshold functions for four different adaptation conditions: light-adapted cones (LAC), dark-adapted cones (DAC), light-adapted rods (LAR) and dark-adapted rods (DAR). The separation between log brightness matches and log thresholds decreased with eccentricity and increased with target size for all adaptation conditions, but overall separation was substantially greater for the DAR condition than for the other three. A two-channel model of achromatic brightness is proposed to explain the results. The model assumes ‘strong’ and ‘weak’ channels, which contribute unequally to brightness. These channels are tentatively identified with tonic and phasic classes of retinal ganglion cells.

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Identification of Long Noncoding RNAs in Distinct Subtypes of Mouse Retinal Ganglion Cells

10.21203/rs.3.rs-147625/v1 ◽

2021 ◽

Author(s):

Ana Ayupe ◽

Felipe Beckedorff ◽

Konstantin Levay ◽

Ramin Shiekhattar ◽

Kevin Park

Keyword(s):

Retinal Ganglion Cells ◽

Ganglion Cells ◽

Axonal Injury ◽

Noncoding Rnas ◽

Small Population ◽

Long Noncoding Rnas ◽

Biological Processes ◽

Retinal Ganglion ◽

Sequencing Data ◽

Specific Expression

Abstract Background: Emerging evidence indicates that long noncoding RNAs (lncRNAs) are important regulators of various biological processes, and their expression can be altered following certain pathological conditions, including central nervous system injury. Retinal ganglion cells (RGCs), whose axons form the optic nerve, are a heterogeneous population of neurons with more than 20 molecularly distinct subtypes. While most RGCs, including the ON-OFF direction-selective RGCs (ooDSGCs), are vulnerable to axonal injury, a small population of RGCs, including the intrinsically photosensitive RGCs (ipRGCs), are more resilient. Results: By performing systematic analyses on RNA-sequencing data, here we identify lncRNAs that are expressed in ooDSGCs and ipRGCs with and without axonal injury. Our results reveal a repertoire of different classes of lncRNAs, including long intergenic noncoding RNAs and antisense ncRNAs that are differentially expressed between these RGC types. Strikingly, we also found dozens of lncRNAs whose expressions are altered markedly in response to axonal injury, some of which are expressed exclusively in either one of the subtypes. Moreover, analyses into these lncRNAs unraveled their neighboring coding genes, many of which encode transcription factors and signaling molecules, suggesting that these lncRNAs may act in cis to regulate important biological processes in these neurons. Lastly, guilt-by-association analysis showed that lncRNAs are correlated with apoptosis associated genes, suggesting potential roles for these lncRNAs in RGC survival.Conclusions: Overall, the results of this study reveal RGC type-specific expression of lncRNAs and provide a foundation for future investigation of the function of lncRNAs in regulating neuronal type specification and survival.

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Intrinsically Photosensitive Retinal Ganglion Cells

Physiological Reviews ◽

10.1152/physrev.00013.2010 ◽

2010 ◽

Vol 90 (4) ◽

pp. 1547-1581 ◽

Cited By ~ 210

Author(s):

Michael Tri Hoang Do ◽

King-Wai Yau

Keyword(s):

Retinal Ganglion Cells ◽

Ganglion Cells ◽

Small Population ◽

Retinal Ganglion ◽

Visual Functions ◽

Rods And Cones ◽

Living Things ◽

Rotation Of The Earth ◽

Life On Earth ◽

And Behavior

Life on earth is subject to alternating cycles of day and night imposed by the rotation of the earth. Consequently, living things have evolved photodetective systems to synchronize their physiology and behavior with the external light-dark cycle. This form of photodetection is unlike the familiar “image vision,” in that the basic information is light or darkness over time, independent of spatial patterns. “Nonimage” vision is probably far more ancient than image vision and is widespread in living species. For mammals, it has long been assumed that the photoreceptors for nonimage vision are also the textbook rods and cones. However, recent years have witnessed the discovery of a small population of retinal ganglion cells in the mammalian eye that express a unique visual pigment called melanopsin. These ganglion cells are intrinsically photosensitive and drive a variety of nonimage visual functions. In addition to being photoreceptors themselves, they also constitute the major conduit for rod and cone signals to the brain for nonimage visual functions such as circadian photoentrainment and the pupillary light reflex. Here we review what is known about these novel mammalian photoreceptors.

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The change of microglia numbers within the mice retina, optic nerve and chiasm following intravitreal AAV2-GFP injection

European Journal of Ophthalmology ◽

10.1177/11206721211049001 ◽

2021 ◽

pp. 112067212110490

Author(s):

Yuanfei Ji ◽

Bo Yu ◽

Yikui Zhang ◽

Wencan Wu

Keyword(s):

Optic Nerve ◽

Intravitreal Injection ◽

Retinal Ganglion Cells ◽

Ganglion Cells ◽

Optic Chiasm ◽

Optimal Concentration ◽

The Other ◽

Retinal Ganglion ◽

Sparse Labeling ◽

Microglial Morphology

Purpose To explore the optimized concentration of AAV2-GFP for sparse transfection of retinal ganglion cells (RGCs) and optic nerve (ON), and to examine the changes of microglial morphology and distribution in the retina, optic nerve and chiasm after injection. Methods We defined the optimal concentration of AAV2-GFP for sparse labeling of RGCs and axons in WT mice. We further explored the changes of microglial morphology and distribution in the retina, optic nerve and chiasm after intravitreal injection in CX3CR1+/GFP mice. Results 14 days after intravitreal injection of AAV2-GFP, live imaging of the retina showed that fundus fluorescence was very strong and dense at 2.16 × 1011 VG/retina, 2.16 × 1010 VG/retina, 2.16 × 109 VG/retina. RGCs were sparsely marked at a concentration 1:1000 (2.16 × 108 VG/retina) and fundus fluorescence was weak. The transfected RGCs and axons were unevenly distributed in the retina and significantly more RGCs were transfected near the injection site of AAV2-GFP compared to the other sites of the flat-mounted retina. Microglia density increased significantly in the retina and part of optic nerve, but not in the optic chiasm. The morphology of microglia was largely unchanged. Conclusions AAV2-GFP was highly efficient and the optimal concentration of sparsely labeled RGCs was 1:1000 (2.16 × 108 VG/retina). After intravitreal injection of AAV2-GFP, the number of microglia increased partly. The morphology of microglia was comparable.

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Biophysical model of axonal stimulation in epiretinal visual prostheses

10.1101/424622 ◽

2018 ◽

Cited By ~ 1

Author(s):

Michael Beyeler

Keyword(s):

Electrical Stimulation ◽

Ganglion Cell ◽

Retinal Ganglion Cells ◽

Ganglion Cells ◽

Small Population ◽

Biophysical Model ◽

Retinal Ganglion ◽

Stimulus Pulse ◽

Perceptual Distortions ◽

Retinal Response

AbstractVisual prostheses aim to restore vision to people blinded from degenerative photoreceptor diseases by electrically stimulating surviving neurons in the retina. However, a major challenge with epiretinal prostheses is that they may accidentally activate passing axon fibers, causing severe perceptual distortions. To investigate the effect of axonal stimulation on the retinal response, we developed a computational model of a small population of morphologically and biophysically detailed retinal ganglion cells, and simulated their response to epiretinal electrical stimulation. We found that activation thresholds of ganglion cell somas and axons varied systematically with both stimulus pulse duration and electrode-retina distance. These findings have important implications for the improvement of stimulus encoding methods for epiretinal prostheses.

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Variability of responses of cat retinal ganglion cells

Visual Neuroscience ◽

10.1017/s0952523800002923 ◽

1992 ◽

Vol 8 (3) ◽

pp. 277-279 ◽

Cited By ~ 10

Author(s):

Michael W. Levine ◽

Brian G. Cleland ◽

Roger P. Zimmerman

Keyword(s):

Firing Rate ◽

Retinal Ganglion Cells ◽

Ganglion Cells ◽

The Other ◽

Retinal Ganglion ◽

Cortical Cells ◽

First Approximation ◽

Abrupt Changes ◽

The Mean ◽

The Difference

AbstractPrevious studies of the varibility of firing of retinal ganglion cells have led to apparently contradictory conclusions. To a first approximation, the variance of rate of maintained discharges of ganglion cells in cat is independent of the mean firing rate. On the other hand, the variability of responses to abrupt changes in lighting of ganglion cells in goldfish increascs with increasing firing rate. To examine whether the difference is due to differences between species, we examined the variablility of responses of cat ganglion cells, and find it similar to that of goldfish ganglion cells. The variance of rate of ganglion cells is neither independent of mean rate, as might be expected from maintained dischargs, nor directly proportional to the mean rate, as it is for cat cortical cells. Rather, there is a monlinear relationship between varience of rate and mean rate.

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